The lushness of flowers blooming in the spring and summer reminds me of the gift of life and how amazing the spirit of growth is. It is especially powerful with fragrant flowers, like jasmine, freesia and stargazer lilies. I am particularly fond of the stargazer lily because lily's last a long time from the date of purchase to the time of throwing them away, therefore maximizing the value of the experience.
Aaron bought me flowers some time ago, and not remembering what I had said I liked, made up a flower name -- the Moonlight Iris -- and brought that to me as a gift. It was a beautiful gift and now iris' are my second favorite flower. I still prefer the intoxicating smells of the lily.
Of course, I also am growing increasingly appreciative of side split right anti-spin flowers and I even got a cool photo of that at the Palace of Fine arts taken by Charles Russo.